The rock strike the water with the speed of 15.78 m/sec.
The speed by which rock hit the water is calculated by the formula
v=
v=
v=15.78 m/sec
Hence, the rock strike the water with the speed of 15.78 m/sec.
The middle or centre of the Earth is the core. However the middle of the layers from the surface to the centre of the Earth is known as mantle.
elasticity stretches and can also return to it's normal size ..
Answer:
change in momentum, 
Average Force, 
Explanation:
Given:
angle of kicking from the horizon, 
velocity of the ball after being kicked, 
mass of the ball, 
time of application of force, 
We know, since body is starting from the rest
.....................(1)


Now the components:


similarly


also, impulse
.........................(2)
where F is the force applied for t time.
Then from eq. (1) & (2)



Now, the components


&


Answer:
The final speed of the crate is 12.07 m/s.
Explanation:
For the first 10.0 meters, the only force acting on the crate is 225 N, so we can calculate the acceleration as follows:


Now, we can calculate the final speed of the crate at the end of 10.0 m:
For the next 10.5 meters we have frictional force:


So, the acceleration is:
The final speed of the crate at the end of 10.0 m will be the initial speed of the following 10.5 meters, so:
Therefore, the final speed of the crate after being pulled these 20.5 meters is 12.07 m/s.
I hope it helps you!